What year do you foresee this happening?
Given CRISPR and other techniques that exist (that we are aware of) and more powerful techniques no doubt being developed, sooner than "AI robots do all the work and we live in heaven" for sure. We don't even have self-driving cars as a practical widely available product yet. Yes there are a lot of proof of concept demos and hype.
I think there will be a crossover where the wealthy realize "wait a second, we can just program biological machines much more quickly and efficiently."
Why focus on really difficult and expensive technologies and machines to manipulate matter on tiny scales when we already have nature's nanobots, ready for programming?
Identifying which genes can be manipulated in which way to produce servile, masochistic slave humans will not be too difficult at all once real resources are thrown at it. So the only barriers are 'moral' and is it realistic to think that such technology will be restricted in use to 'good' minds indefinitely?
Round up a bunch of cattle humans in camps. Identify ones with high resentment, rebellious nature etc at poor treatment. Identify ones with docile temperament, whistle-while-you-work optimism, don't mind being beaten and feel guilty at not pleasing their masters or meeting demands and work extra diligently.
Rather than a long and uncertain breeding program, instead a lot of genetic studies, MRIs, bloodwork, and other analyses can be done on the extremes of temperament. Modifications made very quickly to direct evolution versus the slow route.
It can be accomplished much more quickly, perhaps more importantly, with less intensive resource requirements than building a bunch of AI robot workers. We already
have the machines that you can just feed plant oils and other such flavored cheap feed and nature has already built brains--no need for AI. You just need them to comply more readily.
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